Changing the back angle of the broach cutter when machining eccentric shafts

Abstract

To increase the efficiency of processing eccentric shaft necks, a method has been proposed, the essence of which is to use milling cutters when basing it along the shaft axis. It is assumed that the direction of rotation and the rotation frequency of the shaft and the broach cutter coincide, and the shaping of the eccentric shaft neck will be performed in one turn of the tool. When implementing this processing method, the key task is to create a tool, for which it is necessary to perform a set of theoretical and experimental studies aimed at developing methods for assigning its geometric characteristics and processing modes. Formulas of the initial tool surface, cutting edges, front and back surfaces of the cutter teeth are obtained. The result of modeling the installation of the plane of the front surface for one tooth and for all the cutting teeth of the cutter is shown. Using the developed software, a study was carried out of the changes in: the rear angle during milling at different values of the transverse feed Sm; the rear angle from the longitudinal feed at different values of the rotational speeds of the shaft and the milling cutter. The conducted research allowed us to establish that the teeth of the milling cutter work in various conditions. The application of the developed software will allow to determine the values of the static rear angles on the milling cutter ensuring their change within the contact with the allowance in the specified ordinates of the range.